• Use available information to continually assess current hazard potential related to CNT and CNF exposures in the workplace and make appropriate changes (e.g., sampling and analysis, exposure control) to protect worker health. At a minimum, follow require-ments of the OSHA Hazard Communication Standard [CFR 1910.1200(h)] and the Hazardous Waste Operation and Emergency Response Standard [29 CFR 1910.120].
• Identify and characterize processes and job tasks where workers encounter bulk (“free-form”) CNT or CNF and materials that contain CNT/CNF (e.g., composites).
• Substitute, when possible, a nonhazardous or less hazardous material for CNT and CNF. When substitution is not possible, use engineering controls as the primary method for minimizing worker exposure to CNT and CNF.
• Establish criteria and procedures for selecting, installing, and evaluating the performance of engineering controls to ensure proper operating conditions. Make sure workers are trained in how to check and use exposure controls (e.g., exhaust ventilation systems).
• Routinely evaluate airborne exposures to ensure that control measures are working properly and that worker exposures are being maintained below the NIOSH REL of 1 µg/m3 using NIOSH Method 5040 (Section 6 and Appendix C).
• Follow exposure and hazard assessment procedures for determining the need for and selection of proper personal protective equipment, such as clothing, gloves, and res-pirators (Section 6).
• Educate workers on the sources and job tasks that may expose them to CNT and CNF, and train them about how to use appropriate controls, work practices, and personal protective equipment to minimize exposure (Section 6.3).
• Provide facilities for hand washing and encourage workers to make use of these facili-ties before eating, smoking, or leaving the worksite.
• Provide facilities for showering and changing clothes, with separate facilities for stor-age of nonwork clothing, to prevent the inadvertent cross-contamination of nonwork areas (including take-home contamination).
• Use light-colored gloves, lab coats, and workbench surfaces to make contamination by dark CNT and CNF easier to see.
• Develop and implement procedures to deal with cleanup of CNT and CNF spills and decontamination of surfaces.
• When respirators are provided for worker protection, the OSHA respiratory protec-tion standard [29 CFR 1910.134] requires that a respiratory protecprotec-tion program be established that includes the following elements:
ȣ A medical evaluation of the worker’s ability to perform the work while wearing a respirator.
ȣ Regular training of personnel.
ȣ Periodic workplace exposure monitoring.
ȣ Procedures for selecting respirators.
ȣ Respirator fit testing.
ȣ Respirator maintenance, inspection, cleaning, and storage.
• The voluntary use of respirators are permitted, but must comply with the provisions set forth in CFR 1910.134(c)(2)(i) and CFR 1910.134(c)(2)(ii).
• Information on the potential health risks and recommended risk management prac-tices contained in this CIB should, at a minimum, be used when developing labels and Safety Data Sheets (SDS), as required [http://www.osha.gov/dsg/hazcom].
1.1 Medical Screening and Surveillance
The evidence summarized in this document leads to the conclusion that workers occupation-ally exposed to CNT and CNF may be at risk of adverse respiratory effects. These workers may benefit from inclusion in a medical screening program to help protect their health (Section 6.7).
1.1.1 Worker Participation
Workers who could receive the greatest benefit from medical screening include the following:
• Workers exposed to concentrations of CNT or CNF in excess of the REL (i.e., all workers exposed to airborne CNT or CNF at concentrations above 1 µg/m3 EC as an 8-hr TWA).
• Workers in areas or jobs that have been qualitatively determined (by the person charged with program oversight) to have the potential for intermittent elevated air-borne concentrations to CNT or CNF (i.e., workers are at risk of being exposed when they are involved in the transfer, weighing, blending, or mixing of bulk CNT or CNF, or the cutting or grinding of composite materials containing CNT or CNF, or workers in areas where such activities are carried out by others).
1.1.2 Program Oversight
Oversight of the medical surveillance program should be assigned to a qualified health-care professional who is informed and knowledgeable about potential workplace expo-sures, routes of exposure, and potential health effects related to CNT and CNF.
1.1.3 Screening Elements
Initial Evaluation
• An initial (baseline) evaluation should be conducted by a qualified health-care profes-sional and should consist of the following:
ȣ An occupational and medical history, with respiratory symptoms assessed by use of a standardized questionnaire, such as the American Thoracic Society Respiratory Questionnaire [Ferris 1978] or the most recent.
ȣ A physical examination with an emphasis on the respiratory system.
ȣ A spirometry test (Anyone administering spirometry testing as part of the medical screening program should have completed a NIOSH-approved training course in spirometry or other equivalent training; additionally, the health professional overseeing the screening and surveillance program should be expert in interpreting spirometry testing results, enabling follow-up evaluation as needed.).
ȣ A baseline chest X-ray (digital or film-screen radiograph). All baseline chest images should be clinically interpreted by a board eligible/certified radiologist or other physician with appropriate expertise, such as a board eligible/certified pulmonologist. Periodic follow up chest X-rays may be considered, but there is currently insufficient evidence to evaluate effectiveness. However, if periodic follow up is obtained, clinical interpretation and classification of the images by a NIOSH-certified B reader using the standard International Classification of Radiographs of Pneumoconioses (ILO 2011 or the most recent equivalent) are recommended.
ȣ Other examinations or medical tests deemed appropriate by the responsible health-care professional (The need for specific medical tests may be based on factors such as abnormal findings on initial examination—for example, the findings of an unexplained abnormality on a chest X-ray should prompt further evaluation that might include the use of high-resolution computed tomography scan of the thorax.).
Periodic Evaluations
• Evaluations should be conducted at regular intervals and at other times (e.g., post-incident) as deemed appropriate by the responsible health-care professional based on data gathered in the initial evaluation, ongoing work history, changes in symp-toms such as new, worsening, or persistent respiratory sympsymp-toms, and when process changes occur in the workplace (e.g., a change in how CNT or CNF are manufactured or used or an unintentional “spill”). Evaluations should include the following:
ȣ An occupational and medical history update, including a respiratory symptom update, and focused physical examination—performed annually.
ȣ Spirometry—testing less frequently than every 3 years is not recommended [OSHA NIOSH 2011]; and
ȣ Consideration of specific medical tests (e.g., chest X-ray).
Written reports of medical findings
• The health-care professional should give each worker a written report containing the following:
ȣ The individual worker’s medical examination results.
ȣ Medical opinions and/or recommendations concerning any relationships between the individual worker’s medical conditions and occupational exposures, any special instructions on the individual’s exposures and/or use of personal protective equipment, and any further evaluation or treatment.
• For each examined employee, the health-care professional should give the employer a written report specifying the following:
ȣ Any work or exposure restrictions based on the results of medical evaluations.
ȣ Any recommendations concerning use of personal protective equipment.
ȣ A medical opinion about whether any of the worker’s medical conditions is likely to have been caused or aggravated by occupational exposures.
• Findings from the medical evaluations having no bearing on the worker’s ability to work with CNT or CNF should not be included in any reports to employers.
Confidentiality of the worker’s medical records should be enforced in accordance with all applicable regulations and guidelines.
1.1.4 Worker Education
Workers should be provided information sufficient to allow them to understand the nature of potential workplace exposures, potential health risks, routes of exposure, and instruc-tions for reporting health symptoms. Workers should also be provided with information about the purposes of medical screening, the health benefits of the program, and the pro-cedures involved.
1.1.5 Periodic Evaluation of Data and Screening Program
• Standardized medical screening data should be periodically aggregated and evaluated to identify worker health patterns that may be linked to work activities and practices
that require additional primary prevention efforts. This analysis should be performed by a qualified health professional or other knowledgeable person to identify worker health patterns that may be linked to work activities or exposures. Confidentiality of workers’ medical records should be enforced in accordance with all applicable regula-tions and guidelines.
• Employers should periodically evaluate the elements of the medical screening pro-gram to ensure that the propro-gram is consistent with current knowledge related to ex-posures and health effects associated with occupational exposure to CNT and CNF.
Other important components related to occupational health surveillance programs, includ-ing medical surveillance and screeninclud-ing, are discussed in Appendix B.